Enbrel Use Linked to Inflammatory Bowel Disease in Juvenile Arthritis Patients

Copenhagen, DKThose patients who take Enbrel for arthritis risk a collection of Enbrel side effects including, but not limited to inflammatory bowel disease (IBD) in children suffering from juvenile idiopathic arthritis (JIA). An Enbrel infection of this type appears to present as a high possibility according to a recent study released last month in Copenhagen.

The study, as summarized in the July 15th edition of Elsevier Global Medical News, reviewed the data of 1,515 patients from five European registries located in Denmark, Finland, Germany, Italy and the Netherlands from 1999 through 2007. All patients suffered from JIA and were listed in the various registries as being treated with etanercept—the generic name for Enbrel. They were followed for 2,900 patient-years.

Over the course of the study 18 of the patients developed IBD, with the vast majority of those diagnoses (16 of the 18) confirmed through colonoscopy and pathology. The review excluded any JIA patient who had presented with IBD prior to receiving Enbrel.

The study concluded that the incidence of IBD was roughly 500 cases per 100,000 patient-years of follow-up. According to Dr. Nico M. Wulffraat, the rate is 100-fold higher than in the general population.

He made the comments at the annual European Congress of Rheumatology, held recently in Copenhagen.

"The incidence seems very high," said Dr. Wulffraat, who is affiliated with the University Medical Center Utrecht (the Netherlands). "We need more data to confirm this early finding."

It's possible that IBD is an adverse effect of etanercept treatment, or that IBD is an intestinal complication of JIA, Dr. Wulffraat said. A third possibility is that JIA is an extraintestinal manifestation of IBD, although Dr. Wulffraat said that explanation was unlikely because JIA preceded the appearance of IBD by several years; in one case the interval between diagnosis of JIA and onset of IBD was 12 years.

The high incidence rate in this most recent review contrasts with results from a study published in 2001 in the Lancet that found a population-based IBD incidence of 5.2 per 100,000 person-years in children younger than 16 years from the United Kingdom and the Republic of Ireland who were studied 1998 through 1999.

"The pathology leaves little doubt that this was IBD, and not a transient effect on the colonic mucosa," Dr. Wulffraat said.

The researcher found that the time between the start of Enbrel treatment and the onset of IBD ranged from 9 days to 5 years. Thus, continued concern over Enbrel side effects.